Medical imaging and extraction of anatomy from imaging is important, as evidenced by the many means of medical imaging available. Several imaging techniques involve reconstruction and image enhancement on raw acquired data in order to produce better images. Reconstruction and enhancement may be used to decrease noise in an image, smooth the effects of incomplete data, and/or optimize imaging. Common forms of medical imaging that employ image reconstruction and/or enhancement include computed tomography (CT) scans, magnetic resonance imaging (MR), ultrasound, single positron emission computed tomography (SPECT), and positron emission tomography (PET). One mechanism used to achieve higher-quality reconstruction and enhancement is to use prior information about a target reconstructed/enhanced image. Typically, the prior information takes the form of assumptions about image smoothness or image patches from reference images.
Reference images are often available and used to obtain the prior information. Reference images may include at least a portion of a target anatomy, and portions of reference images may be used to render models of anatomy associated with the target anatomy. For example, reference images may be idealized images, images of a patient associated with a target anatomy (e.g., wherein a target anatomy may include an anatomical part of the patient), images of the anatomical part of other patients, etc. The images may be collected at various times or conditions, and they may have various levels of relevance or resemblance to a specific target anatomy.
Use of the reference images as image patches may mean that reference image use is piecemeal and/or may apply only to regions of an image identified as problematic. Evaluation of whether reference images are suitable for use as image patches may be lacking. In addition, use of reference images only as image patches may mean that unless portions of an image are identified as problematic, the image or various portions of the image may not have the opportunity to benefit from comparison to a reference image.
Accordingly, a need exists for systems and methods for reconstructing and enhancing images based on reference images and associated anatomical models.